About the formula V =[img=73x62]180300d897d52ad.png[/img], which statement is NOT correct? A: [img=12x19]180300d8a0ab3df.png[/img](0) is positive semi-definite B: V is positive semi-definite C: [img=12x19]180300d8a0ab3df.png[/img](j) → 0 as j →∞ D: [img=12x19]180300d8a0ab3df.png[/img](j) =[img=12x19]180300d8a0ab3df.png[/img](-j)

Which estimator is positive semi-definite? 未知类型：{'options': ['long run variance-covariance estimator [img=11x24]17de8379772258d.png[/img]=[img=51x65]17de837982326d0.png[/img]([img=17x47]17de83798f44d1a.png[/img])[img=12x24]17de83799af1362.png[/img](j)', 'OLS', 'Newey and West (1987) HAC estimator', 't test statistic'], 'type': 102}